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Why is there no Char.Empty like String.Empty?
... a reason for this? I am asking because if you needed to use lots of empty chars then you get into the same situation as you would when you use lots of empty strings.
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How to represent empty char in Java Character class
I want to represent an empty character in Java as "" in String...
15 Answers
15
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Not equal != operator on NULL
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As a manual workaround, you could commonly SELECT * FROM MyTable WHERE coalesce(MyColumn, 'x') <> 'x' to assign a constant if it is NULL value, providing you give an appropriate datatype for the sentinel value x (in this case a string/char). This is TSQL syntax ...
What Xcode keyboard shortcuts do you use regularly? [closed]
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Uncommenting only does not work when your selection contains one or more lines that are not already commented.
– DarkByte
Jun 19 '14 at 8:03
a...
.NET / C# - Convert char[] to string
What is the proper way to turn a char[] into a string?
7 Answers
7
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Why do I get a segmentation fault when writing to a “char *s” initialized with a string literal, but
...estion 1.32
Q: What is the difference between these initializations?
char a[] = "string literal";
char *p = "string literal";
My program crashes if I try to assign a new value to p[i].
A: A string literal (the formal term
for a double-quoted string in C
source) can be used in two...
Convert Rows to columns using 'Pivot' in SQL Server
...9, 3, 87);
If your values are known, then you will hard-code the query:
select *
from
(
select store, week, xCount
from yt
) src
pivot
(
sum(xcount)
for week in ([1], [2], [3])
) piv;
See SQL Demo
Then if you need to generate the week number dynamically, your code will be:
DECLARE @c...
How can I remove duplicate rows?
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Assuming no nulls, you GROUP BY the unique columns, and SELECT the MIN (or MAX) RowId as the row to keep. Then, just delete everything that didn't have a row id:
DELETE FROM MyTable
LEFT OUTER JOIN (
SELECT MIN(RowId) as RowId, Col1, Col2, Col3
FROM MyTable
GROUP BY Co...
const char* concatenation
I need to concatenate two const chars like these:
12 Answers
12
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What platforms have something other than 8-bit char?
Every now and then, someone on SO points out that char (aka 'byte') isn't necessarily 8 bits .
12 Answers
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